I've a genuine question that the recent IPCC report has got me wondering...

Over the past 15 years have you changed your mind with regards to AGW?

Did you once support the idea and now don't (or vice versa) or have you always been firmly for or against?

FWIW I've always been firmly on one side of the argument.

I'd love to hear people's views and thoughts on this,  though can I stress that I come to this without agenda and really hope that it doesn't descend into the usual for and against arguments - there is a thread in the climate forum for that.

Mods obviously feel free to move if this is in the wrong place - I posted here because I felt it would get a wider response than the climate forum!

When I first started posting on TWO back in 2002 I was quite sceptical.  These days I have no doubt about AGW though I continue to question attributions, consequences and the extent to which we understand the interaction between various anthropogenic and natural forcings.

Yes, I used to be a climate denier when I understood nothing about the science but was arrogant enough to think that spending 2 minutes on a WUWT blog post made me an expert. I started to change my mind around 4 years ago perhaps, and fully accepted AGW maybe 2 years ago. 

Im still in the camp that if AGW isnt real , and that if it is real - perhaps its nothing more than natural cycles that we don't fully understand yet. I mean - thats a pretty bold statement, considering i have no real acumen in meteorology. Its a gut feeling, nothing more.

Please dont have a go at me for saying so.

If anything, monitoring the weather as i have over the past - say 10-15 yrs, has made me realise that nature balances out over periods of time, and that extremes have always existed, and have always been and will be broken. If anything in periods in the past - extremes by accounts have been worse - and THAT is my main gripe. Weather always proves us wrong....always.

What I see is a major issue in the data collection- is its always improving, and we try and compare that to a very short sample of data (relative to the life of the earth by modern standards) with poor distribution and collection methods (historically).

Is the real problem understanding what is normal for the Earth? Climate has evolved dramatically and eratically over the past billion yrs, and will continue to do so... so if it is changing - are we wrong to stop it? yet we compare a short sample data and ice core samples to understand historically what it might have been like. Compare that to the data we get from the likes of satalites which give such high resolution sample data, and you can see why my gut feels a bit unsure. We're comparing apples with oranges....then a few yrs later bananas and so on.

HOWEVER
If the consequence of this (true or not true) means that people are a little bit more responsible for the environment they are in, that it pushes technology to newer greener economical methods to create energy - then i fully support the thought. Business's will always take the cheapest most economical route to make money. If that means relying on fossil fuels for now - then they will continue to do so.

I was once a bit unsure about it but, like Andy and Quantum, have come to fully accept the science.

I used to take it as gospel that it was happening but now I don't think global warming is happening.  I am willing to be proven wrong as I cannot be sure either way.  I just believe that it is natural climate variability.

I have always accepted the science since I learnt the basics, that view has changed little over the years. I don't think either end of the specturm of future global climate at all likely, so I'd pretty much rule out either no significant warming or catastrophy.

I've always taken the view that warming is a real phenomenon, certainly some natural variability but accentuated by human activity. My opinion of the relative importance of these two has swung back and forth. At the moment I think human activity is th more important factor.

As an aside, at one time I was well in to all the "ancient astronaut" and "atlantis" theories.  I read all the books.  I was quite convinced that an "Earth Crust Displacement" could have happened and that an ancient civilisation existed in what used to be a temperate Antarctica.   The books were very persuasive and those who wrote them provided plenty of evidence ......

....... and then I looked into it myself.   Checked the evidence.   Questioned the evidence.   And now I am a staunch adversary of those who still support what, based on my knowledge of the real science, are poorly contructed arguments based on misunderstandings and old data that has since been superceded, though many still maintain that what was thought true in the 1960s is true today.

It has been a bit like that with AGW.   A similar road.

But of course, I may be wrong.  As may all of us be.   Science is all about disproving what we knew yesterday and who knows what we may learn tomorrow?

I call this the metadata problem Essan. Essentially it works like this, all the good ideas are in the journals which filter into the textbooks and pop science books. The former is pitched at a high level whereas the later at a much lower level. Psedoscience by contrast is all low level stuff (i.e wrong stuff that anyone can understand easily), so what tends to happen is this psedoscience is popular because it is easy to understand, its often free, and a combination of the two give it popularity which gives it, for instance, high ranks on Google. Journal articles by contrast are inaccessible to the public, behind a pay-wall and you have to use a specialized engine to even find them like Web of knowledge or Google scholar. Journals are getting better and have started incorporating social media which is helping to up the quality of their meta data, wikipedia is also a massive help - it wasn't a prominent thing when I was a denier, but nowadays wikipedia is an excellent resource. Unfortunately things like WUWT still have excellent metadata which makes them popular and persuasive. And obviously scientific papers and textbooks don't use persuasive language so the blogs have another advantage there. 

Agree

I have been firmly of the view for about 25 years now that human induced warming is real and is having an impact on our climate. along with many other naturally occurring factors.

I remember way back in the late 80's hearing messages that while we could expect to see a general warming trend what we would also see was much more in the way of extreme weather of all sorts, including severe cold at times. That really resonated with me at the time and in my opinion has been proved absolutely correct.

Nothing I have seen or experienced in the intervening period has changed my original position one bit.

Spend a few weeks in the climate forum.... 

And your position will remain unchanged. 

I think part of this comes down to the debate of what is 'natural' and what is not. For those who argue that it's just natural cycles in our climate, many then ask.. well if it is just natural change in the climate, why are we seeing anomalous trends in the greenhouse gas concentrations in our current interglacial that coincide with anthropogenic activity when compared to previous interglacials? But then a possible answer to that is, well how do we know that the past is a good analogue for the present? Why is the past necessarily representative of what is 'natural'?

Personally, I think it is hard to deny AGW - but the extent to which we are offsetting the 'natural' climate is what is unclear.

Some studies have also suggested that were it not for early anthropogenic activity, such as European forest clearance for early agriculture and the release of Methane in East Asian rice paddies (I'm referring to the Ruddiman hypothesis here), then 'naturally', we should already be well into the next glacial cooling. Whilst this idea is very controversial in its own right, it brings up the debate of whether AGW is actually a bad thing. Wouldn't we be a lot worse off in glacial cooling than in an extended interglacial?

I've always been sceptical of AGW. 

In Roman times grapes were grown as far north as NE England, which would suggest a warmer climate than today. Now if I'm not mistaken there were no cars, coal burning factories back then. Then temps went down from around Anglo Saxon/Viking times.

Now if the impact of people in our country & the rest of the world is having such a great influential effect on warming our climate then why did we have the coldest December in 100 years in 2010? and the coldest March for 50 years in 2013?

I doubt those were flukes, pretty monumental flukes if they were and quite close to each other. 

Overall I don't think the UK climate has changed massively for the worse in all my life. Certainly not enough to cause concern. Our climate has always been very erratic and that's purely due to where we are located.

Nowadays we have the internet, social media and 24 hour rolling news so a flood or an extreme event gets almost instant attention and coverage. 15-20 years ago that wasn't the case - People really weren't "in the know" about what happened 50 miles away or around the world.

And I think that is one of the main factors in all this climate change/AGW thing. Also there is more people on the planet than ever - which means more eyes and more reports. And obviously this means more of an impact when bad weather hits as more people are effected so this gives the impression that an event is worse.

So I think there is a few factors that come into play here. I think man made fuels may add a bit to AGW but I think in the grand scheme of things it's small. I think climate change is 90-95% a natural phenomenon.

Nail on the head there my friend.  People are much more aware of the weather outside of their bubble these days.  Hearing extreme weather phenomena in far flung places and basing a conclusion if its unusual on one event - is a massive problem of social networking - However - it helps with fund raising and such - so is no real issue.   Also there is the problem of miscommunication such that we se in the express and mail.  We dont get hurricanes in this part of the world - but they report like we do.  Hurricanes hitting Newyork... like its never happened before.   Flooding in the UK - where people ae building their houses on flood plains due to cheap land....

all these combine to make a very scary world that seems to be changing for the worse.... but in reality - is it?  Last year the north atlantic hurricane season was non existent.  However that wont be shared on social media because it isnt really exciting news.  however from the peoples perspective - in a couple of years when they have another active year they will only remember the last time it was also very active, and compare the two. hey presto - Why are we always getting hurricanes.

Reminds me of when people say summers used to be hotter when they were a kid, and winters used to be snowier.  Im sorry - but youve just completely forgotten the times with it wasnt, and remembered the times when it was.

(Obviously im talking about the lay person here, and not someone who uses TWO who are a bit smarter, keep records and make level judgements ;) )

Isn't this a classic case of conflating 'weather' and 'climate'?

Even within a period of warming, there will be individual events that in themselves neither prove nor disprove AGW. Similarly, we can't just look at one small region of the planet. The overall trend globally is for warming temperatures. There will be spikes and dips along the way - but the overall trend has been, and is expected to continue to be, upwards.

Yes, we did have warmer temps (in parts of the NH at least) 2000-odd years ago. But then, the Eocene Period was even warmer still - and that was largely down to very high concentrations of GHG's (from volcanic activity)

FWIW, I've always had a basic understanding of the principals of AGW, and to my layman's eyes, the science of 'greenhouse gasses trap heat, and the more GHG's, the more heat is generally trapped' appears sound. Indeed, it is a principle accepted by the vast majority of the scientific community.

However, it is also scientific fact that the Earth goes through climate cycles. My own belief is that AGW is fact, although its specific impact cannot be measured accurately, because we do not know what effect natural climate cycles have on the temp.

Who knows, without AGW, Dec 10 could have been even colder!

Nice to have a thread thats not been trashed yet!

I'm a luke-warmer - pretty sure of the basic physics, happy that man has increased the level of CO2 in the atmosphere and that this may have or is increasing global temperatures, but dismayed by what I see as alarmism and exageration of impacts. I believe that natural processes have been downplayed and CO2 'framed' to some extent in a Poirot type exposition - 'we've eliminated all the other possibles, it MUST be CO2.

I have huge issues with much of what has gone on with all sides of 'climate debate'. Some of the science has been shoddy and I think some of the behaviour has been very poor. I work in a UK science department and I am well aware of the requirements for archiving data and making it available when it is used to support published articles. I will not publish work that I am not happy to send to someone else to scrutinise. For whatever reason climate science has been reluctant to allow this data to be looked at and this must change in the future.

I'm not sure that climate scientists interact enough with statisticians, yet so much of what is published is heavily statistical in nature.

Those outside science (on all sides) have no concept of what peer-review actually means.

Too often extreme weather (and any extreme weather) gets linked to AGW (usually but not exclusively by the media)

Too many times genuine concerns about the science have been dismissed by use of the awful phrase 'deniers' - a phrase so politically charged and resonant with the holocaust that those who use it should be ashamed.

Too many sceptics are too ready to assume conspiracy, and poor motivation amongst climate scientists.

I don't think that the web has helped - its far too easy to be unspeakably rude on the internet - people would be nicer in face to face meetings (as evinced by the recent Bristol dinner...)

To sum up - AGW is probably happening, and has raised temps by a little, with more to come. It probably won't be a disaster though.

All involed should try to be nicer to each other...

WRT to the politicisation of the topic, politicians have of course been quick to jump on the bandwagon for popularity purposes.

But much of the opposition to the AGW theory has been funded - especially in the early days of the debate - by multinational corporations either involved in the supply of carbon-based fuels, or reliant on them.

There has been a concerted propaganda campaign of disinformation & water-muddying by organisations funded by said multinational corporations.

Apart from the obvious, this has politicised the debate in a more subtle way. People whose politics are naturally opposed to the hegemonic power of multinational corporations have allied themselves with the AGW 'side', whilst many of those who dislike the sort of people who are anti-corporation have shown sympathies toward those who deride AGW theory. I'm simplifying it, of course, and there are anomalies on both sides, but it's certainly a trend that I've noticed.

It does seem to make sense, personally I abhor politics interfering like this regardless of which 'side' they are on. There is something amiss when you are using persuasive language to try and convince layman of the public. In an ideal world policy would be based on the scientific evidence, the way it seems to work is that politicians game the evidence to suit their agenda. Unfortunately this is part of the price of being in a democracy, and despite being a bad idea, every other system is much much worse. 

How true. Only this week the Home Office received the report from a study it had commissioned into drug policy. The report said the drug policy is garbage, isn't working (in fact can actually act to increase drug use), and a waste of £billions.

The Home Office didn't just disregard its own study, it denigrated it and publicly announced it would take no sodding notice (sub-text: because it didn't fit with the Tory Party's 1950's Daily Heil attitudes)